Here are my observations on the latest changes to the Comprehensive Rules.
I produced these using fairly crude file comparison tools to identify what
changed and then editing the differences.

There were a lot of changes to the Glossary. About two thirds of this
document covers Glossary changes.

Please don't consider this to be in any way "official". I rushed this out
just prior to leaving for GP San Diego.

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These are rule numbers that did not exist in the April version. These
rules don't necessarily change the way the game is played.
103.2 300.6 410.11
212.2a-d 406.2e 412.3
217.2d 408.g 412.4
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These rule numbers do not exist in the November version.
410.8a
Some triggered abilities watch for a game state, such as a
player's life total or the number of cards in play, rather than
an event. These abilities trigger as soon as the game state
matches their condition (even if it's not otherwise legal to
play a spell or ability at that time). These are called "state
triggers." (Don't confuse state triggers with state-based
effects.)
410.8b
State-triggered abilities don't trigger again until the initial
condition has resolved or been countered. Then, if the permanent
with the ability is still in play and the game state still
matches its trigger condition, the ability will trigger again.
419.8c
[Redundant with 419.8a.]
If multiple replacement effects create a loop, the affected
player or the controller of the affected permanent or zone
decides where to break the loop.
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This section contains rules that have changed enough that I found
something interesting about the change. Indented text has been quoted
directly from the rules.
102.2
Losing because of drawing out is now a state-based effect:
When a player is required to draw more cards than are left in
his or her library, he or she draws the remaining cards, then
loses the game the next time a player receives priority. (This
is a state-based effect. See rule 420, "State-Based Effects.")
214.5
Clarifications about interactions between type-changing abilities and
continuous effects.
The initial value of a permanent's characteristic is the value
printed on the card or specified by the spell or ability that
create the token or changed the type of the permanent. Using a
type-changing ability that says it changes a characteristic
changes the initial values of characteristics stated in the
ability's text, not the current values. Continuous effects that
don't change the type of a permanent affect current values of
characteristics and can override characteristics set by
type-changing abilities.
EXAMPLE: A player plays an artifact's ability that reads "2:
This permanent is a 3/2 artifact creature." Later in the turn,
the artifact creature is affected by an ability that reads
"Target creature is 0/2." At this point, playing the ability of
the artifact again won't do anything; because the type-changing
ability changes characteristics at the initial level, it can't
override the effect. The artifact creature remains 0/2.
214.8d
Used to specify that the "controller" chooses the permanent to enchant,
now it is the player putting it into play.
215.2
Added:
If a "Legendary" noncreature permanent becomes a creature, it
gets the creature type "Legend" for as long as it's a creature.
If a creature of type "Legend" becomes a noncreature permanent,
it's a "Legendary" permanent of the new type. In other words,
they mean the same thing, except that one refers to creatures
and the other to noncreatures.
216.1
Specifies controller and owner of tokens:
Some spells and abilities put a token creature into play. The
token is controlled by whoever put it into play and owned by the
controller of the spell or ability that created it. The rules
text of the spell or ability defines the initial characteristics
of the token it creates. A token's name is its creature type
unless otherwise specified; for example, the creature type of a
Goblin token is Goblin. Once a token is in play, changing its
name doesn't change its creature type, and vice versa.
217.5d
Cards outside the in-play zone aren't controlled by anyone.
300.3
Effects scheduled to last until some phase/step now expire at the
beginning of that phase/step, instead of the end of the preceding
phase/step.
303.1
Specifies that abilities triggering during the untap step go on the stack
at the beginning of the upkeep step.
308.5, 309.3
Added "and all <*> costs have been paid" to the definition of an attacking
or a blocking creature (<*> is "attacking" or "blocking").
310.1b-d
Changed "will deal" to "will assign".
406.1a
Specifies that mana abilities are activated abilities.
406.1b
Added:
Triggered abilities that put mana into a player's mana pool but
trigger from events other than activating mana abilities aren't
mana abilities. They go on the stack and resolve like any other
triggered ability.
408.1b
Added the following about the resolution of state-based effects:
Each time a player receives priority, all applicable state-based
effects resolve (See rule 420, "State-Based Effects"), then
triggered abilities are added to the stack (See rule 410,
"Handling Triggered Abilities"); these steps repeat until no
further state-based effects or triggered abilities are
generated. Then the player may play a spell, ability, or land as
governed by the rules for that phase.
409.1e
Has been generalized to apply to more than just dividing damage.
409.1f
Costs can be paid in any order.
410.2
Clarification of "may" in triggered abilities:
If the ability says a player "may" do something, that player
controls the triggered ability and the pseudospell. If the
ability says this for more than one player, it generates one
pseudospell per player. If the ability doesn't use the word
"may," the controller of the source of the triggered ability
controls the ability (and the pseudospell).
410.5
Rewritten to make much more sense (no longer described as "modal"):
Some triggered abilities give a player a choice of completing an
action or doing nothing (denoted with the word "may"). This
choice is made at the time the ability would be put on the
stack. If the player chooses to complete the action, a
psuedospell is added to the stack. Otherwise, nothing is added
to the stack; the ability is ignored. This doesn't apply to a
triggered ability that requires a player to do something
"unless" that player pays the alternative requirement.
419.5
Added:
Note that the modified event may contain instructions that can't
be carried out, in which case the player simply ignores the
impossible instruction.
419.6b
Corrected description of regeneration to be a "destruction-replacement
effect" instead of a "damage-replacement" effect. Added the following:
Note that if destruction is caused by lethal damage, any
abilities that trigger from that damage being dealt still
trigger even if the permanent regenerates.
420.5a
Added:
...who was required to draw more cards than were in his or her
library...
420.5b
Now effects creatures with less than 0 toughness.
420.5c
Defines lethal damage.
501.3
Added (reminder text).
502.3a
Now specifies when flanking triggers.
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Glossy Change (Detailed Descriptions)
This section covers changes to existing Glossary entries. In general, most
changes involved the addition of a phrase or sentence to the existing
entry. Where this is the case, the added text is simply listed without any
comments from me. Sometimes, such as when there are multiple,
non-contiguous, changes, the entire definition is included.
Some entries reference Appendix B, "Older Rules." These entries are
mentioned below.
Ability
When an effect states that a permanent "gains" or "has" an ability,
it's granting that permanent an ability. If an effect defines a
characteristic of the permanent ("[permanent] is [characteristic]"),
it's not granting an ability.
Active Player
States that the active player does not get priority at for the begin of
untap and clean-up steps.
Artifact Creature
"Artifact" isn't a creature type. Most artifact creatures have no
creature type. Those with a creature type will say "Artifact
Creature - [type]"; for example, "Artifact Creature - Golem."
Attack
Using a spell or ability (even during the combat phase) is never
considered to be an attack.
Banding, Bands with Other (Obsolete)
References Appendix B, "Older Rules."
Snow-covered lands are still basic lands, for example, Snow-Covered
Plains is considered a plains.
Bury (Obsolete)
For most purposes, "bury" is equivalent to "destroy [this
permanent]; it can't be regenerated."
Buyback
New references rule 413.2h.
If for some reason the card wouldn't otherwise go to its
controller's graveyard, it doesn't go to his or her hand; it goes to
wherever it's otherwise destined.
Casting Cost (Obsolete)
The obsolete term "total casting cost" means "converted mana cost."
Characteristics
The word "exclusively" now modifies the list. Added "what it enchants" to
the list of things that are not characteristics.
Color
If an effect gives a permanent a new color, the new color replaces
all previous colors rather than adding to them.
Colorless
Lands and artifacts are colorless because they have either no mana
cost or no colored mana in their mana costs. They can be given a
color by effects.
Comes into Play [Improved definition]
A permanent comes into play when the card or token representing
it is moved into the in-play zone. A permanent whose type or
controller changes doesn't "come into play."
Permanents come into play untapped and under the control of
whoever put them into play.
Instructions that alter permanents coming into play do so as
they come into play. For example, if an instruction causes
something to come into play tapped, it isn't put into play
untapped and then tapped. The controller-to-be of that
permanent makes any choices required by the instruction.
When a permanent comes into play, first apply any "as [card]
comes into play" text, then apply any "[card] comes into
play with" text, then apply continuous effects, then check
to determine if the current form of the permanent generates
any triggered abilities.
Converted Mana Cost
The old term for converted mana cost was "total casting cost."
Cost
..., and so on.
Counts As
...may be tapped for green mana and...
Cumulative Upkeep
Note that if a card has more than one cumulative upkeep cost, each
creates a separate triggered ability at the beginning of upkeep that
counts all the cumulative upkeep counters on the card from both
abilities.
Cycling
Deleted the erroneous part about effecting a spell's resolution.
Damage
Describes damage on noncreature permanents.
Damage-Prevention Ability
...or activated ability...
Discard [Updated]
A player discards a card by putting the card from his or her hand
into his or her graveyard. By default, spells and abilities that
cause a player to discard a card allow the affected player to choose
which card to discard. Some spells and abilities, however, allow
another player to make the choice for a random discard.
Event
The text of triggered abilities and replacement effects defines the
event they're looking for; one "happening" may be treated as a
single event by one ability and as multiple events by another. For
example, if an attacking creature is blocked by two defending
creatures, this is one event for a triggered ability that reads
"Whenever [name] becomes blocked" but two events for a triggered
ability that reads "Whenever [name] becomes blocked by a creature."
Expansion Symbol
Includes a comprehensive list of expansion symbols.
First Strike
Mentions that non-first strike creatures deal damage in a separate step.
Flanking
Changed "that modifies the declare blockers step" to "that modifies the
declare blockers step."
Hand
...that haven't been played yet.
If
Note that the word "if" has only its normal English meaning anywhere
else in the text of a card; this rule only applies to an "if" that
immediately follows the trigger condition.
Leaves Play
References Appendix B, "Older Rules" for phasing.
Main Phase
...also called the "precombat" and "postcombat" main phases.
Mana Symbol
A spell or ability whose cost is 0 must still be played the same way
as one with a cost greater than zero; it won't "play itself
automatically."
Move
A few changes to the second paragraph:
A moved enchantment stops enchanting the previous permanent and
starts enchanting the new one, and it receives a new timestamp.
Nothing else about the enchantment changes. The enchantment never
left play, so no comes-into-play or leaves-play triggered abilities
will trigger. If an ability of the moved enchantment affecting
"enchanted [permanent]" was on the stack when the enchantment moved,
it will affect the new enchanted permanent when it resolves, not the
old one.
Opponent
Changed "player playing the spell" to "player controlling the spell".
Pay
Any time a player is asked to pay mana, mana abilities may be
played.
Also, the resolution of a spell or ability doesn't pay another spell
or ability's cost, even if part of its effect is doing the same
thing as the other cost asks for.
Permanently (Obsolete)
...or it leaves play.
Phased Out (Obsolete)
References Appendix B, "Older Rules."
Phasing (Obsolete)
References Appendix B, "Older Rules."
Priority
The player who has the option to play a spell or ability at any
given time has priority.
Each time a spell or ability (other than a mana ability)
resolves, and at the beginning of most phases or steps, the
active player receives priority. After a player plays a spell,
ability, or land, he or she again receives priority. When a
player passes, his or her opponent receives priority. (If both
players pass in succession the top spell or ability on the stack
resolves, or if the stack is empty the phase or step ends.)
Each time a player receives priority, all applicable state-based
effects resolve (see rule 420, "State-Based Effects") and then
triggered abilities are added to the stack (see rule 410,
"Handling Triggered Abilities"); these steps repeat until no
further state-based effects or triggered abilities are
generated. Then the player may play a spell, ability, or land as
governed by the rules for that phase.
Regenerate
Regeneration is a destruction-replacement effect. "Regenerate
[permanent]" means "The next time [permanent] would be destroyed
this turn, instead remove all damage from it, tap it, and (if it's
in combat) remove it from combat." Because it's a replacement
effect, it must be active before the attempted destruction event.
Note that if destruction is caused by lethal damage, any abilities
that trigger from that damage being dealt still trigger even if the
permanent regenerates.
Set Aside
To set aside a card is to remove it from the game; however, the
effect will specify some condition that allows the set-aside card to
return to the game. See also Removed from the Game.
Skip
...one effect will be satisfied in skipping the first occurrence,
while
the other will remain until another occurrence can be skipped.
Source
The source of an ability or of damage is the card or token that
generated it. If an effect requires a player to choose a source, he
or she may choose either a permanent or a spell on the stack
(including one that creates a permanent) or any card or permanent
referred to by a spell or pseudospell on the stack. The effect will
apply to the next damage dealt by that spell or by that permanent
(in combat or by one of its abilities). A source doesn't need to be
capable of dealing damage to be a legal choice.
State-Based Effects
No longer references the start of a step/phase. This definition is not
comprehensive, as state-based effects are also checked during the Cleanup
Step (i.e. when players don't normally receive priority).
Static Ability
...and has the ability.
Target
A spell or pseudospell on the stack can't target itself.
Type
A land's type is the same as its name.
A local enchantment's type is printed after the word "Enchant"
on the card's type line.
The "type" of mana includes both its color and any restrictions
placed upon it; for example, mana that can be used only to play
artifact spells.
Unblockable
Spells or abilities may still cause it to become blocked.
Vanguard Card
...however, these abilities have no color, and damage from them
isn't damage from a permanent of any type or a source of any color.
A Vanguard card isn't a Magic card, so it can't be affected by
spells or abilities.